Over the last several years it has become apparent that the neurotransmitter serotonin (5-hydroxy-tryptamine--5-HT) is associated directly or indirectly with a number of physiological phenomena, including appetite, memory, thermoregulation, sleep, sexual behavior, anxiety, depression, and hallucogenic behavior [Glennon, R. A., J. Med. Chem. 30, 1 (1987)].
It has been recognized that there are multiple types of 5-HT receptors. These receptors have been classified as 5-HT.sub.1, 5-HT.sub.2, and 5-HT.sub.3 receptors, with the former being further divided into the sub-classes 5-HT.sub.1A, 5-HT.sub.1B, 5-HT.sub.1C, and 5-HT.sub.1D.
We have now discovered a class of compounds which exhibit high binding affinity at the 5-HT.sub.1A receptor. The compounds, by reason of their 5-HT.sub.1A agonist activity, are useful in the treatment, for example, of sexual dysfunction, anxiety, depression, and eating disorders, such as anorexia.